Woodrow Karey, Jr. is shown in this photo after being charged in the shooting death of Pastor Ronald J. Harris, Sr., Saturday, Sept. 28, 2013.

Calcasieu Parish Sheriff's Office/AP Photo

The wife of a deacon accused of gunning down a pastor during a church service had filed a rape complaint against the preacher two days before he was fatally shot, a Louisiana sheriff said today.

Calcasieu Parish Sheriff Tony Mancuso said investigators are trying to determine whether the deacon's wife had a consensual relationship with the pastor or if she had been the vicitim of an assault.

"We are looking at the possibility of that as a motive," Mancuso told ABCNews.com.

He said authorities have seen text messages exchanged between Woodrow Karey's wife and Pastor Ronald J. Harris Sr., and hope obtaining more phone records will shed light on the relationship between the pair.

Karey entered the Tabernacle of Praise Worship Center in Lake Charles, La., Friday evening during the service and initially shot Harris with a shotgun, police said. After striking Harris, Karey allegedly shot him again at close range before fleeing.

The shooting happened during an evening revival service in front of more than 60 congregants, including the pastor's wife, police said.

Kim Myers, the public information officer for the Calcasieu Parish Sheriff's Office, said Karey fled on foot to the end of the street and then called the sheriff's department to turn himself in.

After deputies arrived, Karey showed them the shotgun allegedly used in the shooting in addition to a .22-caliber pistol that he had hidden in a wooded area.

He was arrested without incident on a charge of second-degree murder and held on $1 million bail. According to police he has no previous arrest record.